Qbank (16 Questions)

(SBQ12.8)
A 45-year-old patient complains of leg pain associated with the pathology seen in Figure A. The patient undergoes microdiskectomy. During surgery there is no evidence of instability. Ten months later he
re-develops similar symptoms of leg pain. A repeat MRI is consistent with a recurrent lumbar disc herniation. Which of the following most accurately describes the outcomes of revision surgery in comparison to primary surgery?
Review Topic

The clinical presentation is consistent with a recurrent lumbar disc herniation. Revision lumbar discectomy has been shown to have outcomes (pain and function) equal to that of primary lumbar discectomy.

Recurrent lumbar disc herniation is a common complication of lumbar discectomy procedure. These entities may initially be treated with anti-inflammatories, physical therapy and rest. If those initial measures do not work, selective nerve root injections can be used (epidural/selective nerve blocks). If these measures fail, then revision lumbar discectomy is the best surgical option; if there is evidence of instability at the level in question, a fusion procedure would be indicated.

Stambough et al. review management of recurrent lumbar disk herniations. They note that the majority of these cases can be treated conservatively. In cases where surgery is indicated, revision lumbar discectomy is the procedure of choice.

Patel et al. retrospectively reviewed 30 patients who had undergone primary and revision lumbar spine discectomy. Outcomes assessed were Visual Analogue Scales for back and limb pain (VAB & VAL) and the Oswestry Disability Index (ODI). They found similar, statistically significant improvements in limb pain and ODI scores. They conclude that revision discectomy can achieve results as good as those after primary discectomy.

Figure A shows a sagittal T2 weighted MRI sequence of a disk herniation at the L4-L5 level.

Incorrect AnswersAnswer 2, 3, 4, 5: Revision lumbar discectomy has been shown to have as good outcomes in terms of pain and function as primary lumbar discectomy.

Question Comments

(OBQ12.102)
In patients with a symptomatic lumbar disc herniation who have failed nonoperative management, which of the following patient characteristics are associated with improved treatment effects with surgery?
Review Topic

Age > 41 years, absence of joint problems, and married status are associated with improved treatment effects in patients having surgery for lumbar disc herniation.

Lumbar disc herniations are a common cause of low back and leg pain. In the vast majority (>90%) the symptoms improve with nonoperative treatment within 3 months. However, a subset of patients have persistent pain and require surgery. Variables have been associated with outcomes with surgical treatment. The most frequently described is that workers compensation patients have worse surgical outcomes.

Weinstein et al. in the SPORT study found that in a combined as-treated analysis at 4 years, patients who underwent surgery for a lumbar disc herniation achieved greater improvement than nonoperatively treated patients in all primary and secondary outcomes except work status.

Pearson et al. in the SPORT study found the following patient characteristics were associated with improved treatment effects with surgical intervention for lumbar disc herniation: age > 41 years, absence of joint problems, a high school education or less, no worker’s compensation, duration of symptoms for over 6 months, being married, worsening symptom trend at baseline, and Mental Component Score (MCS) of less than 35.

Nguyen et al. looked at a cohort of Worker's Compensation patients and their outcomes following lumbar fusion. They found lumbar fusion for the diagnoses of disc degeneration, disc herniation, and/or radiculopathy in a Workers Compensation setting is associated with significant increase in disability, opiate use, prolonged work loss, and poor RTW status.

Illustration A shows the two most common positions of a lumbar disc herniation (paracentral-blue and foraminal-red). Illustration B shows a paracentral disc herniation at L4/5 on an axial MRI and shows how it affects the descending (L5) nerve root. Illustration C shows a foraminal disc herniation at L4/5 on an axial MRI, and how it affects the exiting (L4) nerve root.

Question Comments

(OBQ12.230)
A 38-year-old male presents with a three month history of low back pain and right leg pain that has failed to improve with nonoperative modalities including selective nerve root corticosteroid injections. Leg pain and paresthesias are localized to his buttock, lateral and posterior calf, and the dorsal aspect of his foot. On strength testing, he is graded a 4/5 for plantar-flexion and 4+/5 to ankle dorsiflexion. On flexion and extension radiographs there is no evidence of spondylolisthesis. Sagittal and axial T2-weighted MRI images are shown in Figure A and B. Which of the following treatment modalities will allow the greatest improvement of physical functioning?
Review Topic

The clinical presentation is consistent for a lumbar disc herniation with symptoms of a combined L5 and S1 radiculopathy that has failed to improve with extensive nonoperative treatment. At this time a discectomy would lead to the greatest improvement in physical functioning.

Anderson et al. reviewed the adequacy of randomized controlled studies completed over 25 years (1983-2007) that attempted to compare discectomy with non-surgical treatment. Given the high crossover rates and heterogeneity of outcome measures, the authors are unable to make conclusions as to the benefit of one treatment modality over another.

Weinstein et al. reviewed greater than 1000 patients who had imaging confirmed lumbar disc herniations; treatment modalities were non operative or operative (discectomy). Significant improved in physical function, bodily pain and disability scales were seen at even 4 years postoperatively.

Figures A and B show the axial and sagittal sequences of a T2-weighted MRI of the lower lumbar spine. A large L5/S1 para-central disc herniation is seen that has migrated cephalad. Therefore, it is irritating both the exiting L5 nerve root and descending S1 nerve root.

Incorrect answersAnswers 1, 2, 3: Many (> 90%) disc herniations have a self-limited natural history; the symptoms may be alleviated by bedrest and activites as tolerated, administration of anti-inflammatories or GABA analogs and completion of physical therapy. For symptoms that persist greater than 6 weeks and are disabling, surgery is indicated. Recent data from the SPORT trial suggests that functional outcomes may be improved by completion of discectomy. Answers 5: Completion of a discectomy and instrumented fusion is not indicated in this patient. Without evidence of degenerative changes in the lumbar spine or evidence of spondylolisthesis, a posterior spinal instrumented fusion is not warranted.

Question Comments

(OBQ11.65)
A 33-year-old woman reports pain down her right leg and numbness across the dorsum of her right foot which started 3 months ago during a bowel movement. Prior to this she had had 1 month of low back pain. She had a lumbar microdiscectomy at L4/5 3 years ago which was successful. On physical exam she has weakness to ankle dorsiflexion and great toe extension on the right. Her new MRI images are shown in Figure B. After a failure of nonoperative treatment, which of the following is the most appropriate surgical treatment?
Review Topic

The clinical presentation is consistent with a recurrent lumbar disc herniation. If conservative measures fail, the most appropriate treatment is revision microdiskectomy.

Papadopoulos et al. looked at a total of 27 patients who had undergone revision discectomies for recurrent lumbar disc herniation. They foundrevision discectomy is as successful as primary discectomy for patient satisfaction and function.

Suk et al. studied conventional discectomy for treatment of recurrent lumbar disc herniation and found results to be comparable to discectomy for a primary herniation.

Incorrect Answers: Answer 2: A L4/5 microdiskectomy with far lateral Wiltse approach is indicated in a far lateral or foraminal disc herniation. An example of a far lateral disc herniation is shown in Illustration A. Answer 3,4,5: A fusion would not be indicated at this time, as there is no sign of instability or spondylolisthesis.

Question Comments

(OBQ11.236)
A 35-year-male presents with pain radiating down the left leg, worse in the anterior leg distal to the knee. On physical exam, he is unable to go from a sitting position to a standing position with a single leg on the left, whereas he has no difficulty on the right. His patellar reflex is absent on the left, and 2+ on the right. Which of the following clinical scenarios would best produce this pattern of symptoms?
Review Topic

This clinical scenario describes a patient presenting with an L4 radiculopathy. This is supported by his decreased patellar reflex and quadriceps weakness. A L4-5 foraminal (far lateral) herniated nucleus pulposis would most likely cause symptoms in the L4 distribution as foraminal herniations most commonly affect the exiting upper nerve root at a given lumbar level.

Rainville et al performed a study to identify the most sensitive physical exam test to detect quadriceps weakness caused by either an L3 or L4 radiculopathy. They found in L3 and L4 radiculopathies, unilateral quadriceps weakness was detected by the single leg sit-to-stand test in 61%, by knee-flexed manual muscle testing in 42%, by step-up test in 27% and by knee-extended manual muscle testing in 9% of patients. They conclude in L3 and L4 radiculopathies, unilateral quadriceps weakness was best detected by a single leg sit-to-stand test.

Deyo et al review the history, presentation, physical exam findings, and conservative treatment aimed at lumbar disk herniations. They describe the treatment modalities recommended (NSAIDS and early progressive mobilization) and those which are not recommended (narcotics and muscle relaxants). Physical examination maneuvers aimed at ruling out a diagnosis of cauda equina syndrome are imperative to understand and document as cauda equina syndrome is a surgical emergency.

Illustration A shows the location of different types of disk herniations. The red circle shows the location of a foraminal (far lateral) disc herniation. The blue circle shows the location of a paracentral disc herniation. Illustration B shows a T2 axial image of a foraminal (far lateral) disc herniation. Illustration C shows a T2 axial image of a paracentral disc herniation. Illustration D describes the difference between the cervical spine and lumbar spine with respect to nerve root anatomy.

Question Comments

(OBQ10.18)
Following surgical treatment of a lumbar disc herniations with radiculopathy, patients with worker's compensation claims have which of the following when compared to patients who do not have worker's compensation claims at 5 years?
Review Topic

1.
Equivalent relief from symptoms and equivalent improvement in quality of life

3% (62/2030)

2.
Less relief from symptoms and less improvement in quality of life

67% (1355/2030)

3.
Improved relief from symptoms and greater improvement in quality of life

Patients with worker's compensation claims have less relief from symptoms and less improvement in quality of life following surgical treatment of lumbar disc herniations. Despite this, they have near equivalent return to work status at 4 years.

Atlas et al. (2000) found patients who had been receiving Workers' Compensation at baseline had significantly less relief from symptoms and less improvement in quality of life, however, they were only slightly less likely to be working at the time of the four-year follow-up.

Question Comments

(OBQ09.206)
A 40-year-old female presents with right leg pain localized to the buttock, posterior thigh, and lateral calf. In addition, she describes numbness and tingling on the dorsum of the right foot. Physical exam shows weakness to EHL. Three months of nonoperative treatment including anti-inflammatory medication, physical therapy, and selective nerve root corticosteroid injections failed to provide lasting relief and pain is still severe in nature. Her MRI is shown in Figures A and B. What would be the most appropriate management at this juncture?
Review Topic

The patients clinical presentation and imaging studies are consistent with a L5 radiculopathy caused by a right paracentral disc herniation at L4/5 which is compressing the L5 nerve root. Because she has failed nonoperative management a laminotomy and diskectomy would be the most appropriate treatment.

A L4/5 paracentral disc involves the L5 nerve root. The muscles innervated by L5 nerve root include EHL and tibialis anterior, and therefore these patients may present with a "foot drop". While EHL is usually innervated by L5 alone, tibialis anterior has variable innervation by L4 and L5.

Weinstein et al. (SPORT 2 year results) showed as-treated analysis (prospective nonrandomized), discectomy was favorable with quicker improvement in symptoms for patients with surgery. They warn that the SPORT intent-to-treat analysis (prospective randomized) showed no statistical difference between those who had diskectomy vs. those who did not, but this data was disrupted by a very high crossover rate, and therefore most consider the as-treated analysis as a more accurate representation of the true clinical effect of treatment.

Weinstein et al (SPORT 4 year results) showed in the as-treated analysis that patients treated surgically for intervertebral disc herniation showed significantly greater improvement in pain, function, satisfaction, and self-rated progress over 4 years compared to patients treated non-operatively. They found at four years there was no significant difference in work status between the surgical and nonsurgical group.

Weber et al. look at a cohort that was randomized into surgical and non-surgical treatment for lumbar disc herniations. They found the controlled trial showed a statistically significant better result in the surgically treated group at the one-year follow-up examination. After four years the operated patients still showed better results, but the difference was no longer statistically significant.

Illustration A shows the lower extremity dermatomes. Illustration B shows how a laminotomy is used to access the disc and how an paracentral disc will affect the descending nerve root. Illustration C shows the difference between a laminotomy, hemilaminectomy, and laminectomy.

Question Comments

(OBQ09.235)
A 45-year-old male comes into your clinic complaining of right leg radicular pain that extends to the dorsal aspect of his right foot. On physical exam he has slight decreased sensation on the top of his right foot as well as 3/5 strength in his right EHL. He has 5/5 strength in the all other muscle groups in his lower extremities and symmetric 1+ patellar and Achilles reflexes bilaterally. Which axial MRI would be consistent with the patients symptoms
Review Topic

The patient presents with a right sided L5 radiculopathy. The only axial MRI image that would cause a right L5 radiculopathy is Figure E, a far lateral L5/S1 disc herniation.

Radiculopathy secondary to a herniated lumbar disc can affect either the traversing nerve root or the exiting nerve root. Paracentral disc herniations are most common, and they affect the traversing nerve root, i.e. an L5/S1 paracentral disc herniation will cause S1 symptoms. Occasionally disc herniations are far lateral. In these cases, the disc herniation affects the exiting nerve root, i.e. an L5/S1 far lateral disc herniation will cause L5 symptoms.

Tamir et al reported that far lateral disc herniations are more common at L3/4 than L4/5 or L5/S1. Additionally, L3/4 disc herniations are more likely to be in older patients, and neurologic deficits are common.

Rhee et al. published a review on the anatomy, pathophysiology and treatment options for lumbar herniated discs.

Illustration A is a schematic showing how paracentral and far lateral disc herniations affect the traversing and exiting nerve roots respectively. Illustration B labels the anatomic structure in the axial MRI in Figure E.

Incorrect Answers: Answer 1: This is a far lateral disc herniation at L4/5. This would present with right L4 symptoms Answer 2: This is a facet cyst at L4/5. It would present with left L5 symptoms Answer 3: This is a paracentral disc herniation at L3/4. This would present with right L4 symptomsAnswer 4: This is a paracentral disc herniation at L5/S1. This would present with right S1 symptoms

Question Comments

(OBQ08.158)
In patients with lumbar disc herniations resulting in significant unilateral leg pain but no functionally limiting weakness, surgical decompression has what long term effects when compared to nonoperative management?
Review Topic

1.
Worse outcomes in pain, physical function, and return to work status at 4 years.

6% (51/891)

2.
Equivalent outcome in pain and physical function at 4 years.

34% (300/891)

3.
Improved outcome in pain and physical function at 4 years.

54% (484/891)

4.
Improved outcome in return to work status only at 4 years.

2% (20/891)

5.
Worse outcome in return to work status with equivalence in pain and physical function at 4 years.

Recent evidence now supports that patients who undergo surgery for lumbar disc herniation have improved outcomes in bodily pain and physical function at 4 years.

Weinstein et al showed in the as-treated analysis that patients treated surgically for intervertebral disc herniation showed significantly greater improvement in pain, function, satisfaction, and self-rated progress over 4 years compared to patients treated non-operatively. They found at four years there was no significant difference in work status between the surgical and nonsurgical group.

Incorrect Answers:Answer 1,2 &5: Surgical patients have improved outcomes in pain, physical function, at 4 years.Answer 4: There is no difference in work status at 4 years.

This is a basic anatomy question. A far lateral disc herniation affects the exiting nerve root. At the L4/5 level this would be the L4 nerve root. The L4 nerve root innervates knee extension, the patellar reflex, and a sensory distribution that travels over the knee into the anterior shin. (see illustration A). Illustration B demonstrates the ASIA Classification of Spinal Injury diagram which also depicts ankle dorsiflexion as a test for L4.

Question Comments

(OBQ06.43)
45-year-old manual laborer presents to the office with acute onset back pain that radiates to his right leg after carrying a heavy object. He also has mild non-progressive weakness with ankle dorsiflexion on that side. A representative MRI cut is shown in Figure A. What should be his initial treatment?
Review Topic

Lumbar disc herniation is the most common cause of radicular pain in the adult working population. 95% of these herniations involve L4/5, L5/S1 lumbar disc spaces. Patients typically present with low back pain and sharp stabbing leg pain with sensory symptoms in a specific dermatomal distribution. Persistent intractable pain following non-surgical treatment during a minimum 6 week period is the most frequent indication for surgery.

The Weber article was a RCT over 10 yrs of 126 pt with sciatica due to herniated lumbar discs. The results of surgical treatment were significantly better than the results in the conservatively treated group after one year of observation, however this difference became much less pronounced after nine more years.

Saal et al retrospectively reviewed 11 patients treated nonoperatively with lumbar disc extrusions through CT/MRI to evaluate disc morphology initially and at follow up (mean 25 mos). Only 1 patient had progression of stenosis, and all patients had disc dessication at the level of disc herniation with contiguous levels being normally hydrated. All patients had a decrease in neural impingement.

Question Comments

(OBQ04.167)
A 34-year-old male has 7 months of right-sided radicular pain to his anteromedial shin and medial ankle which has failed non-operative treatment. Physical exam shows a foot drop and decreased patellar reflexes on the affected side. A MRI is shown in figures A & B. Operative treatment should include:
Review Topic

The clinical presentation and MRI images demonstrate a right-sided far lateral disc herniation at L4/5. As opposed to a paracentral disc which would affect the L5 nerve root, a far lateral disc herniation will affect the L4 nerve root as it exits the L4/5 foramen. That means that the standard midline approach will not easily allow access laterally. Therefore, the Wiltse paraspinal approach is ideal, which preserves segment stability by avoiding injury to the lamina and facet joints. The potential complication to know from the Wiltse approach is potential dorsal root ganglia injury resulting in dysesthesias.

Illustration A and B show the normal and abnormal findings on the MRI images in the question stem. Illustration C shows the advantage of a far lateral approach in gaining access and visualization of the neural foramen from an outside-in trajectory.